The invention pertains to positive displacement engines, and in particular, to positive displacement engines having an integrated or interconnected rotary fluid compressor.
The inventor""s prior U.S. Pat. No. 3,101,888 discloses a combined positive displacement engine and positive displacement rotary compressor apparatus having a straight-sided piston within a combustion chamber having a rectangular cross-section. A single rotary compressor element is eccentrically pivotally mounted on a crankshaft within a substantially circular compressor housing. The compressor element is pivotally connected to the piston whereby oscillation of the piston induces rotation of the compressor element about the cankshaft which compresses air in the compressor housing. The compressed air is expelled through a valve and can be directed to perform work.
The present invention provides improvements in the design of combined positive displacement engines and rotary compressors. The engine of the present invention includes a straight-sided piston disposed within a piston chamber having a rectangular cross-section, and two opposed compressor elements which are eccentrically pivotally mounted on separate, but interconnected crankshafts within a substantially figure-8-shaped compressor chamber housing. Each compressor element is pivotally mounted to the piston whereby oscillation of the piston induces synchronized counter rotation of the compressor elements about their respective crankshafts.
During compression of fluid by the compressor elements, the compressor elements rotate on their respective crankshafts toward one another compressing fluid (e.g., air) therebetween. At a point of minimum clearance between the compressor elements, fluid between the compressor elements is compressed to a maximum pressure and is expelled through an exhaust valve disposed in the compressor housing adjacent the area in which the compressor elements meet. The fluid can be directed into the piston chamber to scavenge exhaust gases from the combustion chamber and to supercharge the chamber. Further, the fluid can, before or after passing through the piston chamber, be directed to the performance of work.
The engine preferably includes two separate compressors (with a total of four compressor elements), linked to separate pistons, which pistons can share a common piston chamber. The crankshafts of each compressor are interconnected and timed causing the pistons to oscillate in opposite directions, synchronously. The dynamic forces of the engine are balanced by the opposing compressor elements of each compressor, by the opposing pistons and compressors, and by counterweights mounted on the crankshafts.
The engine of the present invention is light-weight, efficient, simple to manufacture, and suitable for many uses where fluid power is desired, particularly in aerospace, automotive and construction industries. The invention is particularly suitable for automotive and aerospace applications because the engine provides quick throttle response, whereby power is quickly and readily available.